Pump



Jan 6, 1959 K. R. LUNG 2,867,173

PUMP Y Filed April 29. 1955 FIG-1 v 25 SIS IN V EN TOR.

KENNETH R. LUNG BY w M, M-

ATTORNEYS United States Patent P Kenneth R. Lung, Dayton, Ohio, assignorto The Tait Manufacturing Company, a' corporation of Ohio ApplicationApril 29, 1955, Serial No. 504,783

z Claims. (cl. s- 87) This invention relates to sump or drain pumps,vand more particularly to such pumps of the submersible type wherein themotor is mounted in close relation with the impeller housing forsubmergence in the liquid in the space to be drained.

It is a primary object of the invention to provide a submersible sumppump of the type embodying a centrifugal impeller driven on a verticalaxis by a motor located above the impeller housing wherein the motorcasing and the impeller housing are releasably coupled together by asimple and effective mechanism facilitating their disconnection forservicing, and wherein special provision is made for screening solidmaterial from access to this connection between the motor casing andimpeller housing as well as from access to the pumping chamber itself.

It is also an object of the invention to provide a submersible sump pumpas outlined above wherein a screen member is mounted in engagement withboth the motor casing and the impeller housing to screen solid materialfrom access to the connection therebetween as well as to the inlet tothe pumping chamber in the impeller housing, and wherein this screenmember is constructed and arranged to minimize the development of forcestending to cause solid material from collecting on and/or penetratingthrough the screen.

Additional objects and advantages of the invention will be apparent fromthe following description, the accompanying drawing and the appendedclaims.

In the drawingl Fig. 1 is a view generally in vertical section throughthe motor casing and impeller housing of a submersible sump pumpconstructed inaccordance with the present invention; and

Fig. 2 is a section on the line 2 2 of Fig. 1.

Referring to the drawing, which illustrates a preferred embodiment ofthe invention, the pump includes an mpeller housing 10 and a motorcasing comprising upper and lower sections 11 aud 12 bolted together insealed relation at 13. The upper casing section 11 supports the motorstator 15, which is suspended therein by means of bolts 16, and thiscasing section also supports the control switch for the motor, which isactuated by a lever arm 21 mounted on the outside of the casing and byits associated weight 22 and iloata 23 on a cord 24, reference beingmade in this connection to my copending application Serial No. 504,782filed of even date herewith and assigned to the same assignee as thisapplicacation now Patent No. 2,748,220 issued May 29, 1956. Theelectrical supply conduit 25 to the motor enters the casing section 11through a sealed plug 26, and thus the stator 15 and its entireassociated electrical parts and connections are independent of the lowercasing sec'- tion 12 and may be removed therefrom as a unit for anynecessary service.

The drive shaft of the motor supports the rotor 31 and is in turnsupported by a pair of bearings 32 and 33 in the housing sections 11 and12 respectively.

The lower end of shaft 30 projects through a boss 35 depending fromhousing section 12 and cooperating with the shaft to mount a rotary seal36 sealing the interior' of the motor housing against access of liquidalong the shaft. This seal is supplemented -by the bearing 33, whichincludes sealing disks 37 and 38 carried by the outer race thereof andoverlying the ball-receiving space therethrough to minimize pressureleakage in either direction'through bearing 33.

The impeller housing 10 includes a split boss portion 40 at its upperend which ts over the motor housing boss and is secured thereto by astrap type clamp 41 and clamp bolt 42. The bottom wall Vof the impellerhousing is provided by a removable metal plate 44 which also mayconveniently include a downwardly extend` ing flange portion 45 formingthe base of the unit, the plate 44 being bolted directly to housing 10at 46. The interior of housing 10 forms a pumping chamber 50 havinginlet passages 51 through the vupper portion of the housing between theribs 52 connecting boss 40 with the lower part of housing 10. Agenerally tangentially arranged outlet passage 53 leads from chamber 50for connection with a discharge pipe 54.

Within the pumping chamber 50 is the impeller 55, which is shown as castor molded from a suitable plastic material such as a phenolic resin andwhich includes a shroud portion 56 forming the bottom of the impellerand a plurality of upwardly extending curved vanes 57. The impeller issplined on the lower end of shaft 30 by means of a key 5S to provide forlimited axial movement' of the impeller with respect to the shaft,reference being made in this connection to my copending applicationSerial No. 504,781 led of even date herewith and assigned to the sameassignee as this application. A curved abutment 59 on the under side 0fthe impeller supports it on the bottom plate 44 when the pump is atrest, and in operation, the pressure developed between the shroud 56 andplate 44 causes the impeller to rise out of engagement with plate 44 forfree rotation in the pumping chamber.

Screening means are provided in accordance with the invention forscreening solid material from access both to the inlet passages 51 andalso to the clamped connection between the motor casing and the impellerhousing. This screening means comprises a cylindrical perforate screen60 which encircles the space between the impeller housing and the motorcasing. The lower casing section 12 is formed with a depending annularshoulder 61 having a cylindrical outer surface 62 forming a seat for theupper end of screen 60, and a similar cylindrical seat 63 is provided byan upstanding boss portion 64 on the impeller housing 10 outside andbelow the inlet passages 51. Thus the screen 60 engages both of theseseats and is releasably secured in engagement therewith by simpledetachable means such as'a pair of sheet metal screws4 65 connecting theoverlapping ends of the perforate sheet which forms the screen 60.

It will be seen that this screen construction offers important practicaladvantages in use. Since the screening area is large in comparison withthe flow area through the inlet passages S1, the average suctionelective at each point along the face of the screen is correspondinglylower than the suction through the inlet passages, thus having a reducedtendency to draw solid sediment through this screen. In addition, withthe screening surface essentially vertical, solid particles in theliquid being pumped are unlikely to stick to the screen surface but willmore naturally be drawn by gravity to the bottom of the space beingpumped,.namely below the level of the inlet passages to the pumpingchamber. At the same time, this screening unit is of simple constructionand is also simple tof remove andV replace in connection with anyservicing requirements, l

While the form of apparatus herein described, constitutes a preferredembodiment of the invention, it is tol be understood that theinvention'is not limited to this precise formof apparatus, and thatchanges may be made'y therei'without departing from the scope of theinvention which is,` dened in the appendedA claims.

What is claimed is:

1. A submersible pump of the character described comprising an impellerhousing including a pumping chamber having an inlet in the upper portionof said housing, a substantially Water-tight motor casing having motorparts therein vincluding a drive shaft projecting downwardly therefrom,a tubular boss' depending from said casing'in surrounding relation withsaid shaft and of substantially smaller diameter than said casing, saidimpeller housing-r including a tubular boss extending upwardly therefromabove and' radially inwardly of said inlet,rs aid housing boss beingsplit and proportioned to telescope over the lower end ofsaid casingboss, means forreleasably clamping said bosses together in telescopedrelation tov form the entire vsupport for said casing on said housingwith said drive shaft extending therethrough into saidv pumping chamber,said casing having an annular shoulder on the lower end thereofsubstantially concentric with and of substantially greater diameter thansaid -boss thereon, means forming on said housing a peripheral surfaceylocated radially outwardly of said inlet and -matching the radiallyouter peripheral surface of Said shoulder in aligned relation therewith,and a tubular perforate screen encircling and seating on said peripheralsurfaces to screen solid particles from access to said bosses andY tosaid pumping chamber inlet.

`2. A submersible pump of the character described comprising an impellerhousing including a pumping chamber having an inlet in the upper portionof said housing, a substantially water-tight motor casing including acupshaped lower ycasing section, an upper casing section proportioned toseat on the upper end of said lower casing t 4 I section, a motor statorlocated within said casing, means securing said stator directly to saidupper casing4 section independently of said lower section, a controlswitch for said motor also supported entirely within said upper casingsection, a rotor positioned within said stator and including a driveshaft journaled in both said casing sections and projecting downwardlyfrom said lower section, said lower section. including a tubular bossdepending therefrom in surrounding relation with said shaft and ofsubstantially smaller diameter than said section, said impeller housingincluding a tubular boss' andA a tubular perforate screen encircling andseating on said peripheral surfaces to. screen solid particles fromaccessto said bosses and to said pumping chamber.

References Cited in the file of this patent UNITED STATES PATENTS2,121,299 Peters lune 21, 1938 2,361,747 Curtis et al. Oct. 3l, 19442,394,860 Korte Feb. 12, 1946 2,417,197 Hewitt et al. Mar. 11, 19472,662,206 Schaefer Dec. 8, 1953 2,722,892 French Nov. 8, 1955 2,744,466Difford May 8, 1956 FOREIGN PATENTS 651,619 Great Britain Apr. 4, 1951

